DESCRIPTION: (Adapted from the applicants description) This application is in response to RFA HD-96-09 (Adolescent Medicine HIV/AIDS Research Network). The investigators propose to contribute their cohort of youths and adolescents as well as their experienced clinical research faculty to the existing adolescent health research network. Because there is very little data collected about HIV-infected adolescents, there is a need for additional research and analysis of assist in developing therapeutic interventions that are targeted at adolescents who are infected with HIV. Through this application, the investigators will enroll 30 HIV-infected and 10 uninfected adolescents, who are pre-existing, standardized clinical, for laboratory research protocol. To accomplish these aims, they will build upon the already established structure developed by the Division of Adolescent and Young adult medicine. The investigators state that this model program, structured around a three-pronged approach, inter-related programmatic approach to service delivery, is designed to address HIV-related outreach, risk reduction, diagnosis and treatment needs of at-rick adolescents. The support of this cooperative agreement will enable DAYAM, in collaborative with the Division of Allergy, Immunology and Infectious Diseases, to participate in the basic science and clinical research aimed at studying the medical, psychosocial and biobehavioral aspects of HIV/AIDS in adolescents who are infected via sexual and drug taking practices.